// Copyright (c) Six Labors.
// Licensed under the Six Labors Split License.

using System.IO;

namespace SixLabors.Fonts.Tables.AdvancedTypographic {
  /// <summary>
  /// A LigatureGlyph table contains the number of carets and the offsets to their caret value tables
  /// for a single ligature glyph.
  /// <see href="https://learn.microsoft.com/en-us/typography/opentype/spec/gdef#ligature-glyph-table"/>
  /// </summary>
  internal sealed class LigatureGlyph
  {
      /// <summary>
      /// Gets or sets the array of offsets to caret value tables for this ligature glyph.
      /// </summary>
      public ushort[]? CaretValueOffsets { get; internal set; }

      /// <summary>
      /// Loads the <see cref="LigatureGlyph"/> from the binary reader at the specified offset.
      /// </summary>
      /// <param name="reader">The big endian binary reader.</param>
      /// <param name="offset">Offset from the beginning of the LigGlyph table.</param>
      /// <returns>The <see cref="LigatureGlyph"/>.</returns>
      public static LigatureGlyph Load(BigEndianBinaryReader reader, long offset)
      {
          reader.Seek(offset, SeekOrigin.Begin);

          ushort caretCount = reader.ReadUInt16();
          return new LigatureGlyph()
          {
              CaretValueOffsets = reader.ReadUInt16Array(caretCount)
          };
      }
  }
}